Enteric Coronavirus Infection and Treatment Modeled With an Immunocompetent Human Intestine-On-A-Chip

Abstract

Many patients infected with coronaviruses, such as SARS-CoV-2 and NL63 that use ACE2 receptors to infect cells, exhibit gastrointestinal symptoms and viral proteins are found in the human gastrointestinal tract, yet little is known about the inflammatory and pathological effects of coronavirus infection on the human intestine. Here, we used a human intestine-on-a-chip (Intestine Chip) microfluidic culture device lined by patient organoid-derived intestinal epithelium interfaced with human vascular endothelium to study host cellular and inflammatory responses to infection with NL63 coronavirus. These organoid-derived intestinal epithelial cells dramatically increased their ACE2 protein levels when cultured under flow in the presence of peristalsis-like mechanical deformations in the Intestine Chips compared to when cultured statically as organoids or in Transwell inserts. Infection of the intestinal epithelium with NL63 on-chip led to inflammation of the endothelium as demonstrated by loss of barrier function, increased cytokine production, and recruitment of circulating peripheral blood mononuclear cells (PBMCs). Treatment of NL63 infected chips with the approved protease inhibitor drug, nafamostat, inhibited viral entry and resulted in a reduction in both viral load and cytokine secretion, whereas remdesivir, one of the few drugs approved for COVID19 patients, was not found to be effective and it also was toxic to the endothelium. This model of intestinal infection was also used to test the effects of other drugs that have been proposed for potential repurposing against SARS-CoV-2. Taken together, these data suggest that the human Intestine Chip might be useful as a human preclinical model for studying coronavirus related pathology as well as for testing of potential anti-viral or anti-inflammatory therapeutics.

Human organs-on-chips for disease modelling, drug development and personalized medicine

“…Moreover, when lined with duodenal or colon organoid-derived epithelial cells, these mechanically active microfluidic chips more closely resemble human small and large intestine than organoids cultured in static microphysiological systems (either 3D ECM gel or transwell cultures) based on transcriptomic and histological characterization 36 , 37 , 68 . In a study on infection with an enteric coronavirus (NL63), organoid-derived intestinal epithelial cells were found to also dramatically increase their ACE2 receptor levels when cultured under flow in the presence of peristalsis-like mechanical deformations in two-channel microfluidic intestine chips compared to when cultured statically as organoids in 3D gels or in transwell inserts 70 . A two-channel human intestine chip lined by Caco-2 intestinal epithelial cells interfaced with endothelium was used to study SARS-CoV-2 infection and to reconstitute the morphological, structural and inflammatory changes consistent with gastrointestinal symptoms observed in patients with COVID-19 (ref.…”

Human Organoids and Organs‐on‐Chips for Addressing COVID‐19 Challenges

“…[ 38 , 130 ] A human intestinal chip showed increased ACE2 protein levels under flow and mechanical deformation conditions, enabling to model enteric coronavirus infection. [ 131 ] These intestinal chips integrated with immune cells reflected viral‐induced barrier dysfunction and inflammatory response that other in vitro models cannot achieved. They offered useful preclinical platforms for studying virus related pathology and potential therapeutics testing.…”

Engineering viral genomics and nano-liposomes in microfluidic platforms for patient-specific analysis of SARS-CoV-2 variants

“…Once the villi were established, the apical medium promoted the differentiation of microvascular endothelial cells present in the human large intestine. Furthermore, gut-on-a-chip was used as a-proof-of-concept targeting Human coronavirus NL63 (HCoV-NL63), as a model of SARS-CoV-2 infection for drug testing 105 . Nafamostat, a protease inhibitor, was observed to reduce viral entry, likely via inhibiting the host TMPRSS2 receptor while remdesivir was toxic to the endothelium 105 .…”

“…Furthermore, gut-on-a-chip was used as a-proof-of-concept targeting Human coronavirus NL63 (HCoV-NL63), as a model of SARS-CoV-2 infection for drug testing 105 . Nafamostat, a protease inhibitor, was observed to reduce viral entry, likely via inhibiting the host TMPRSS2 receptor while remdesivir was toxic to the endothelium 105 . Overall, microfluidic platforms open the doors for investigating secondary and systemic drug toxicity in the physiological microenvironment 106 , 107 .…”